Police said the crime was believed to have taken place between the hours of 9pm and 1am the following morning (April 24), with the burglar thought to have gained entry via an open window.

The police investigation is now focusing on identifying the perpetrator - who targeted the WW2 veteran's home in Howletts Lane - using CCTV footage, which shows the offence unfolding.

The footage, comprised from 30 cameras, shows the suspect circling the building twice before making his decision on which flat to break into.

DC Tim Costello, of Hillingdon burglary squad, spoke exclusively to getwestlondon this week about the investigation and the suspect.

He said: "The suspect is a white male with dark hair and of relatively slim build.

"I'd say he almost has sharp features, the face doesn't appear chubby at all.

"I would estimate anything from 5ft 9ins-6ft2ins and his chin is quite rounded.

"I suspect this was an opportunist act, that's my feeling.

"At this point we are looking at a number of people as points of interest who are known to police.

"We take all calls seriously. If anybody provides us with any details we'll respect the caller's details accordingly and we will do our due diligence before we make an arrest."

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DC Costello offered his advice to residents on how to avoid becoming a burglary victim: "People sometimes make the vital mistake of leaving windows open and are surprised by how small a gap burglars can get into, burglars are very adept at opening PVC doors and windows.

"A great deterrent is having an alarm system, we rarely get calls from victims where an alarm has been installed. The only times have been when they've forgotten to turn it on."

DC Costello's tips for staying safe from burglars in the borough:

Don't leave windows open in your house, especially if you go away

If you can, invest in an alarm system

Don't leave expensive items on display

Know your neighbours and look out for your neighbours

If you see someone suspicious outside, call police on 101

DC Costello warns that thieves are opportunists, so "make sure you don't offer these people an opportunity to have a peek inside".

He added: "Don't be afraid to call police. Sometimes our British reluctance to get involved gets in the way of doing the neighbourly thing."